Apparatus for and Method of Detecting Abnormality in Exhaust Gas Temperature Sensor
AssigneeNissan Diesel Motor Co., Ltd.
InventorsHideki Matsunaga, Toshikazu Katou
Life of this patent
Estimating the term…
Abstract
On the basis of a correlation between exhaust gas temperature detected by an exhaust gas temperature sensor and exhaust gas temperature estimated according to an engine operating condition, it is detected whether or not abnormality occurs in the exhaust gas temperature sensor. Namely, when a change characteristic of the detected exhaust gas temperature follows a change characteristic of the estimated exhaust gas temperature, it is determined that the exhaust gas temperature sensor is normal. On the other hand, when the change characteristic of the detected exhaust gas temperature does not follow that of the estimated exhaust gas temperature, it is determined that the exhaust gas temperature sensor is abnormal.
Claims9
An apparatus for detecting abnormality in an exhaust gas temperature sensor, comprising:
- an exhaust gas temperature sensor for detecting exhaust gas temperature of an engine;
- and
- a control unit, including a computer, adapted to execute:
- an exhaust gas temperature estimating process for estimating exhaust gas temperature according to an engine operating condition;
- a transient state determining process for determining whether or not the estimated temperature is in a transient state in which the exhaust gas temperature changes;
- and
- an abnormality determining process for determining, when the transient state determining process determines that the estimated temperature is in the transient state, whether or not abnormality occurs in the exhaust gas temperature sensor on the basis of a correlation between a change characteristic of the exhaust gas temperature estimated by the exhaust gas temperature estimating process and a change characteristic of the exhaust gas temperature detected by the exhaust gas temperature sensor.
A method of detecting abnormality in an exhaust gas temperature sensor, comprising:
- estimating exhaust gas temperature according to an engine operating condition;
- and
- determining whether or not the estimated temperature is in a transient state where the exhaust gas temperature changes, to thereby determine, when it is determined that the estimated temperature is in the transient state in the determination, whether or not abnormality occurs in the exhaust gas temperature sensor on the basis of a correlation between a change characteristic of the estimated exhaust gas temperature and a change characteristic of the exhaust temperature gas detected by the exhaust gas temperature sensor.
Dependencies are inferred from the claim text.